Apparatus for drying continuous webs of textile material



April 20, 1965 APPARATUS FOR DRYING CONTINUOUS WEBS OF TEXTILE MATERIAL Filed Jan. 25, 1962 E. J. HOWLETT 3,1 78,831

United States Patent 3,178,831 APPARATUS FOR DRYING CONTINUOUS WEBS 0F TEXTILE MATERIAL Edward John Howlett, 16 Hillway Highgate London N. 6, England Filed Jan. 25, 1962, Ser. No. 168,611 Claims priority, application Great Britain, Feb. 16, 1961, 5,777/ 61 2 Claims. (CI. 3486) This invention has reference to an improved method of and apparatus for drying continuous webs or sheets of textile and other materials, and is particularly applicable to the drying of webs of textile towelling after the same has been washed.

The drying of continuous webs or sheets of various materials by passing them around hot rollers or over hot chests is well known. Hitherto it has been the practice to employ hollow rollers or chests heated from the interior such as by introducing steam into the same. It Will be appreciated that, in order to obtain the heat flow through the wall suflicient of the hollow member to maintain the necessary high drying temperature on the working surface of the chest or external periphery of the roller, a very high internal temperature will have to be produced necessitating a thick wall to withstand the comparatively high steam pressure contingent upon the internal temperature. The present invention which deals with rollers realises that heat flowing from the external surface of the roller, which alone is required for drying the web lying in contact with such surface, can be produced without the need for conduction through the roller wall, and consequently the said invention adopts the application of direct heating to the outside periphery of the roll.

Although individual sheets can equally well be dealt with by the invention, the term continuous web or simply web will be used hereinafter to embrace such sheets, because in order to deal with them in a continuous flow around a roller, they would be placed on a continuous travelling band.

The present invention consists of apparatus for drying continuous webs of textile material comprising a closed drying chamber, a rotatable hollow perforated roller dis posed within said chamber, web feed and discharge slots respectively in opposite walls of said chamber on opposite sides of said roller positioned so as to guide a web around not more than 180 of the perforated pe riphery of the roller thereby leaving the remaining part of the periphery uncovered by the web, a heat generator mounted within the chamber and located outside the roller immediately adjacent the part of the periphery of the same which will be uncovered by the web, said heat generat-or providing dry heat applied directly to the outer surface of the roller making said outer surface the hottest zone of the thickness of the roller wall, air inlet and outlet openings in the chamber Walls to provide an air throughout for scavenging and carrying away moisture abstracted by the hot roller, the air inlet opening being directed towards the side of the roller against which the heater is located and the air outlet opening facing the diametrically opposite side of the roller.

In order that the said invention may be readily understood two embodiments thereof will be described with the aid of the accompanying drawings in which:

FIGURE 1 is a diagrammatic vertical section of one embodiment, and

FIGURE 2 is a similar view of a second embodiment.

Like numerals of reference indicate the same or corresponding parts in the two views.

In FIGURE 1 there is shown a chamber 1 having an ice air inlet 2 and air outlet 3. Within the chamber there is rotatably mounted a roller 4, heated externally by a suitable source of dry heat which, for example, is a heat generator in the form of an elongated gas burner 5 which extends along the roller from end to end parallel to the axis thereof and having a line of burner holes or nozzles 6 directing their naked flames on to the periphery of the roller. Slotted openings 7 and 8 in opposite walls of the chamber 1, eg in the top and bottom of the chamber respectively constitute feed and discharge slots for the web 9, and said openings are located on opposite sides of roller 4, i.e. more or less on the vertical diameter of the roller 4 so that the web 9 is guided partially around the roller so as to leave part of the periphery of the roller uncovered by the web, ie the left hand side of the roller in FIGURE 1. The gas burner 5 is located adjacent the roller so as to apply its heat to this uncovered part.

The air entering the inlet 2, which becomes heated from the gas fired heat generator 5 also used to heat the roller, may be led (after passing through the chamber 1 and out at 3) to a heat exchanger so as to preheat fresh air conducted to the air inlet of the chamber or to a succeeding chamber. In this latter respect as seen in FIGURE 2 a plurality of chambers 1 may be employed each having a roller 4 and a gas heater 5 together with the other features described in connection with the single chamber as in FIGURE 1, and the web 9 is led from one chamber to another as illustrated through a slot 10 in a wall common to adjacent chambers, said slot constituting both the web discharge slot of one chamber and the web feed slot of the adjacent chamber. The hot wet air exhausted from one chamber is used to pre-heat the fresh air drawn or forced into an adjacent chamber, by means of heat exchangers 11.

It will be seen that the web 9 is passed round not more than of the roller periphery using the side of the roller facing the air discharge opening 3. As stated already, this leaves the remainder of the roller periphery free of the web and this faces the air inlet 2 of the chamber. In place of the gas burner 5 other heat generators, such as an oil burner or electrical heating elements may be employed.

The slots 7 and 8 in the chamber wall for the passage of the web are advantageously designed to minimise the escape of air. For this purpose, with a sheet metal chamber 1 the lips of each slot may be beaded, curled or rolled so as to touch respectively on each side of the web; in fact the web may be caused to be deflected slightly out of line at the slot without imposing too much frictional restraint on its movement.

The rollers may be driven to bring about the Web feed through the apparatus, or may run freely and the web pulled therearound.

To facilitate attention to the roller or rollers and to train the web around the same when commencing a run, the roller may be mounted so as to be journalled at one end only on a supporting structure from which it extends cantilever-wise into the chamber with its projecting shaft extending through a wall thereof, and the casing of the chamber built around the same with a door through which ready access may be gained into the interior of the chamber.

A thermostatic device for turning off the fuel supply to the burner or burners (or cutting out an electrical heater) can be incorporated so as to come into operation should the rotation of the roller inadvertently cease.

In such a case the roller might become over-heated and scorch the Web, and the thermostat would be set to come into operation when a predetermined temperature was exceeded.

It will be seen in FIGURE 1 that the roller 4 is hollow and perforated to permit the air current to pass through the roller and web as well as around the same, thus carrying away moisture extracted from the web by the hot roller.

I claim;

1; Apparatus for drying continuous webs of textile thereby leaving the remaining part" of the periphery un-x covered by the web, a heat generator; mounted withinv each chamber and located outside the rollerimmediately adjacent the part of the periphery of the same which will be uncovered by the web, said heat generator providing dry heat applied directly to the outer surface" of;

the roller making said outer surface the-hottest zone of the thickness of the roller wall, air inlet and outlet openings in thewalls of the chambers to provide an air throughput for scavenging and carrying away moisture abstracted by the hot roller, the air inlet opening being directed towards the side of the, roller againstwhich the heater is located and the air outlet opening facing the diametrically opposite side of the roller, the chambers being so disposed that adjacent chambers have a common wall, in which the web discharge slot of one chamber is located and constitutes the web feed slot of the adjacent chamber. V

2. Apparatus for drying continuous webs of textile material as claimed in claim 1 in which the hot wet air exhausted from one chamber is used to preheat the fresh air drawn or forced into anadjacent chamber.

7 References Cited by the Examiner UNITED STATES PATENTS NORMAN YUDKOFF, Primary Examiner. 

1. APPARATUS FOR DRYING CONTINUOUS WEBS OF TEXTILE MATERIAL COMPRISING A PLURALITY OF CLOSED DRYING CHAMBERS, A ROTATABLE HOLLOW PERFORATED ROLLER DISPOSED WITHIN EACH CHAMBER, WEB FEED AND DISCHARGE SLOTS RESPECTIVELY IN OPPOSITE WALLS OF SAID CHAMBERS ON OPPOSITE SIDES OF SAID ROLLER POSITIONED SO AS TO GUIDE A WEB AROUND NOT MORE THAN 180* OF THE PERFORATED PERIPHERY OF THE ROLLER THEREBY LEAVING THE REMAINING PART OF THE PERIPHERY UNCOVERED BY THE WEB, A HEAT GENERATOR MOUNTED WITHIN EACH CHAMBER AND LOCATED OUTSIDE THE ROLLER IMMEDIATELY ADJACENT THE PART OF THE PERIPHERY OF THE SAME WHICH WILL BE UNCOVERED BY THE WEB, SAID HEAT GENERATOR PROVIDING DRY HEAT APPLIED DIRECTLY TO THE OUTER SURFACE OF THE ROLLER MAKING SAID OUTER SURFACE THE HOTTEST ZONE OF THE THICKNESS OF THE ROLLER WALL, AIR INLET AND OUTLET OPENINGS IN THE WALLS OF THE CHAMBERS TO PROVIDE AN AIR THROUGHPUT FOR SCAVENGING AND CARRYING AWAY MOISTURE ABSTRACTED BY THE HOT ROLLER, THE AIR INLET OPENING BEING DIRECTED TOWARDS THE SIDE OF THE ROLLER AGAINST WHICH THE HEATER IS LOCATED AND THE AIR OUTLET OPENING FACING THE DIAMETRICALLY OPPOSITE SIDE OF THE ROLLER, THE CHAMBERS BEING SO DISPOSED THAT ADJACENT CHAMBERS HAVE A COMMON WALL IN WHICH THE WEB DISCHARGE SLOT OF ONE CHAMBER IS LOCATED AND CONSTITUTES THE WEB FEED SLOT OF THE ADJACENT CHAMBER. 